package demo1;

import java.util.Random;
import java.util.Scanner;

public class demo_6 {
    public static String getCodes(int n){
        StringBuilder sb = new StringBuilder();
        String a = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabdefghijklmnopqrstuvwxyz";
        Random r = new Random();
        for (int i = 0; i < n; i++) {
            sb.append(a.charAt(r.nextInt(62)));
        }
        return sb.toString();
    }

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        String rs = getCodes(n);
        System.out.println(rs);
        sc.close();
    }
}
